There are many applications today where electronic keys are used. A common example is with vehicles where an electronic key, sometimes in the form of a “fob” is enabled by the user to lock and unlock the vehicle doors, trunk, etc., raise and lower windows, start and stop the engine and/or perform a variety of other functions. Such systems are well known in the art.
The present invention is described for the case of electronic keys used to authorize vehicle door access, trunk access, and starting, but this is merely for convenience of explanation and not intended to be limiting. Persons of skill in the art will understand based on the description herein that the present invention applies to any electronic key function and not merely to a “lock” and “unlock” function and not merely to vehicles. Hence, such other electronic key functions are intended to be included in the words “lock” and “unlock” and such other locations, equipment, structures and/or apparatus are intended to be included in the word “vehicle.”
While prior art electronic keys and key systems are useful, they suffer from a number of limitations, well known in the art. Among these limitations is the presence of multiple keys. For example, when multiple keys exist and one or more is left behind in the vehicle (or structure), security can be compromised if an unauthorized person gains access to the “left-behind” key. Even if the vehicle is locked if there is an unauthorized entry and the intruder gains access to the left-behind key, he or she may be able to open doors, turn off a security alarm, start the vehicle or otherwise perform those functions able to be controlled by the left-behind key. Thus, a need continues to exist for improved systems and methods for dealing with multiple keys so that left-behind or other temporarily un-needed keys do not represent a security risk.
Accordingly, it is desirable to provide an improved electronic locking and key system and method that mitigate the risk presented by left-behind keys or other keys whose use may be compromised. It is desirable that the system be able to temporarily invalidate electronic keys that are left-behind or that otherwise present a security risk. In addition, it is desirable that the improved system and method be generally compatible with prior art electronic key systems. Furthermore, other desirable features and characteristics of the present invention will become apparent from the subsequent detailed description and the appended claims, taken in conjunction with the accompanying drawings and the foregoing technical field and background.